Physical Training in Sedentary Middle-aged and Older Men II. Oxygen Uptake, Heart Rate, and Blood Lactate Concentration at Submaximal and Maximal Exercise

Forty-two subjects (34–50 years old) were studied before and after an 8–10 weeks' conditioning program. Maximal oxygen uptake increased in all subjects, mean increase from 2.89 l/min to 3.44 l/min. Maximal pulmonary ventilation increased by 15 per cent to 128 l/min. This increase was brought about by an increase in the respiratory rate from 42 to 46. Heart rate at a given submaximal effort on the bicycle ergometer was 10–20 beats/min lower after training, and mean maximal heart rate was lowered from 193 to 186 beats/min. The blood lactate concentration at a given submaximal oxygen uptake was lower after the training program but not when related to the relative work load. The lower the initial level for the maximal oxygen uptake the larger was the improvement in the maximal oxygen uptake after training.